1. Field of the Invention
The present invention relates to a turbo compressor including a motor and an impeller which is rotationally driven as the rotative power of the motor is transmitted thereto, and a refrigerator including the turbo compressor.
Priority is claimed on Japanese Patent Application No. 2008-27072, filed Feb. 6, 2008, the content of which is incorporated herein by reference.
2. Description of the Related Art
As refrigerators which cool or freeze objects to be cooled, such as water, a turbo refrigerator or the like including a turbo compressor which compresses and discharges a refrigerant by impellers is known.
The turbo compressor included in such a turbo refrigerator or the like has a configuration in which an impeller or a motor for acquiring the rotative power which rotationally drives the impeller is surrounded by a housing, as shown in Japanese Patent Unexamined Publication No. 2007-177695.
Meanwhile, the turbo compressor needs to supply lubricant to sliding parts, such as a gear unit for transmitting the rotative power of the motor to the impeller, in order to make the operation smooth.
The lubricant supplied to the sliding parts is once recovered to an oil tank provided separately from the housing surrounding the motor or impeller for reuse, and is supplied again to the sliding parts.
However, the oil tank is provided separately from the housing which surrounds the motor or impeller as described above. For this reason, when the turbo compressor is assembled, the process of connecting the oil tank to the housing is required, and thus, the assembling process of the turbo compressor becomes complicated.
Additionally, in the turbo refrigerator or the like, chlorofluocarbon is often used as the refrigerant. Consequently, in order to more reliably prevent leakage of the chlorofluocarbon that is the refrigerant, the inside of the housing is sealed. However, when the oil tank is connected to the housing as described above, securement of sealability becomes difficult since connecting portions are created. As a result, advanced measures which improve the sealability are required in the connecting portions, or it is necessary to frequently perform maintenance.
The invention has been made in view of the above problems, and aims at easily improving sealability inside a housing in a turbo compressor.